This message shows up on my Windows 8 RTM folding machine today. I only found it because I explicitly invoked Windows Update to see if there was anything new waiting for my action.

Restart your PC to finish installing updatesYour PC will automatically restart in 2 days if you don't restart now

Users in corporate MDI-managed environments can get this message for critical patches. I understand that, and I support it.

But THIS is the first I've seen it on any of my personal machines!

Whether it is caused by Windows 8 or by Windows Update, I'd sort of like to have a LESS ANNOYING choice.

I'm running folding right now, so when one or more of my folding machines auto-reboots someday when I'm not looking, they'll sit at the Windows password prompt all day/week/month waiting for my input. So then one day [sarcasm]next March[/sarcasm], I'll see my folding machines all waiting for passwords, and then there will be a million new updates to get and I'll have to do it all over again.

BIF wrote: So then one day [sarcasm]next March[/sarcasm], I'll see my folding machines all waiting for passwords, and then there will be a million new updates to get and I'll have to do it all over again.

Sitting at the login prompt the machines should be getting updates in the background and rebooting 2 days later.

The forced reboot is annoying but don't kid yourself, at least they are giving a message now rather than just doing it... there have been many Wednesdays I come home from work (post patch Tuesday updates) and find my machine rebooted from updates.